A simple and fast dns cache server written by go.
Similar to dnsmasq, but supports some difference features:
Keep hosts records in redis and the local file /etc/hosts
Auto-Reloads when hosts configuration is changed. (Yes, dnsmasq needs to be reloaded)
Installation & Running
$ go get github.com/kenshinx/godns
$ cd $GOPATH/src/github.com/kenshinx/godns $ go build -o godns
$ sudo ./godns -c ./etc/godns.conf
$ dig www.github.com @127.0.0.1
$ sudo vi /etc/resolv.conf nameserver #the ip of godns running
All the configuration in
godns.conf is a TOML format config file.
More about Toml :https://github.com/mojombo/toml
Upstream server can be configured by changing file from somewhere other than "/etc/resolv.conf"
[resolv] resolv-file = "/etc/resolv.conf"
namerservers are set in resolv.conf, the upsteam server will try in a top to bottom order
Domain-specific nameservers configuration, formatting keep compatible with Dnsmasq.
More cases please refererence dnsmasq-china-list
Only the local memory storage backend is currently implemented. The redis backend is in the todo list
[cache] backend = "memory" expire = 600 # default expire time 10 minutes maxcount = 100000
Force resolve domain to assigned ip, support two types hosts configuration:
- locale hosts file
- remote redis hosts
can be assigned at godns.conf,default :
[hosts] host-file = "/etc/hosts"
Hosts file format is described in linux man pages.
More than that ,
*. wildcard is supported additional.
This is a special requirment in our system. Must maintain a global hosts configuration, and support update the host records from other remote server. Therefore, while "redis-hosts" be enabled, will query the redis db when each dns request is reached.
The hosts record is organized with redis hash map. and the key of the map is configured.
[hosts] redis-key = "godns:hosts"
Insert hosts records into redis
redis > hset godns:hosts www.test.com 18.104.22.168
Compared with file-backend records, redis-backend hosts support multiple A entries.
redis > hset godns:hosts www.test.com 22.214.171.124,126.96.36.199
$ go test -bench=. testing: warning: no tests to run PASS BenchmarkDig-8 50000 57945 ns/op ok _/usr/home/keqiang/godns 3.259s
The result : 15342 queries/per second
The test environment:
CentOS release 6.4
Intel Xeon 2.40GHZ 4 cores
Joke: A web console for godns
Deployment in productive supervisord highly recommended.
[program:godns] command=/usr/local/bin/godns -c /etc/godns.conf autostart=true autorestart=true user=root stdout_logfile_maxbytes = 50MB stdoiut_logfile_backups = 20 stdout_logfile = /var/log/godns.log
- The redis cache backend
- Update ttl
godns is under the MIT license. See the LICENSE file for details.